Fin construction



Sept? c, E. LUCKE 2,33%,065

FIN CONSTRUCTION Filed Oct. 8, 1941 INVENTOR Charles E..Zuc1e -k mm.

ATTORNEV end is not o be eke'n' as limiting cirre- *ders fio thereby minimize the lesees m flahe' r rrgy Of a. engine {cylinder owing Patented Sept. 21, 1943 2,330,065

s PATENT:: OFHC'E srmmr; e e

e United Aircraft: Gorporzi tion; a'ist @Har tfrd, "cenn a cij'iliy'biiafiqn of P512, V H

#Applaemermewhe s, 1941-,iSe1fiwl No. -'.4M,,1:41 j Y -t -wiww-i pi t This i nv'erition relates to f-impreveifier itfi 'in heat heat meme-2e -1oies i$uchas= cylinders tralns ferdevices and has particular reternce to with external anrimarfins fie Etrenfifiemring :heat imprevements in heat transfer evice's er an exfrom the cylinders to a strear n'sef eoolingrairiflowtar-many finned cylindrical type s ueh ems-the mg =paetdihe-mymide1 smnd it ts also known to NITED 'ders 0f *interna l-combilstion' errgrhes. 1 5 mrovide j aickets or -befiesfim ddsing m fi fihe mter- An object of the invention reeiii'e'e'dnthe iaro- "(i-wind spaces and eenstreimngwem e time 'air vis'ien of an improved fin ainii jacket etmbture "fiassiing threugh'the e ri'gine to flow thmu'g h the for heat exchange devices, euc'hes meeene eem- "inter fie epaces areun d the 'iengriilseeylinderes end bust-ion engine cylinders, partictilafly'arrfifid "cylinder-heads. 2m ali ktlewfi arx elngeementsthe to reduce energy losses-in the ficiWbfcotiHmgair 1-0 particu lerly tne eyti r iter barrel me, xwppl'iedtothe devices. Y tend entirelyerourid tfiein dividualewfimiiersemd A further object resides in the eeevieme of maintain substanttallythwsame madialflepth'and improved heat transfer a 6 air eontrtflfirrg -"t'he=sa fiie speeimg fe-r tne eeteeew-meer c'ireum- "means (if the character 1 cated iaafitietiler'rl'y tenant-Wand the=coblmg=aiirfefitramce s'pwees' prodesi gfiedto improve the-fiietfibutioh-efcbdlirrg -15 'v i'd'ed the baiffl'es or jajekets expese the periair aridfiadilitete the eIi-try ofFthe aHfirf-tefarfd J "her'ielelges df the fi'ns-toitkfe errtering strealm of cit-it dfthe'heat tran'sfer'strudtu-re. w eyrmeer elin'g a- It is cendeived- -thait this Ether objects emu advantages Wi11*- be 'more e 'rrenge c aus'es lalrge lessee in we en'ergy articularly "pointed *out nereirieffter 'pr wiilfeef ei r s firafin alndds also reepen'eible come apparent as the descriptien'hroed for an' mnequel ifistfibfifiien of air finw aromd In the accompanying drawing; in I the elpiteeideeof tlre vafidus ve ylmders aknde, reference numerals are used to desig fivte sjerrfiler fme'tiiation df ee'ol ingjei ir fiew over pa'ifitieufler 0 11-- parts throughout, "there is il luetrated, "in 'SeVeTaI meereree stantially or actually in contact with the peripheries thereof, the jacket portions terminating at the corresponding sides of the fin notches, as is clearly illustrated, to provide air entrance and 7/ exit openings in the jacket structure. Along'the edges of these openings the edges of the jacket portions are slightly curved and ,may be bent at some suitable location and which may include exhaust gas actuated means for inductively increasing the fiow of cooling air through the engme.

It is also contemplated to provide vanes or separators, as indicated at 42 and 43 in Fig. 1, to divide the airflow and insure an equal flow of air around the opposite sides of the various cylinders in those installations where there is a tendency for the air to divide unequally or to fluctuate in its passage in opposite directions around the individual cylinders.

Such vanes or dividers may be applied to all of the cylinders in inwardly into positive contact with the fin pe-M ripheries, as is particularly shown in Fig. 1, or

' maybe beaded outwardly, as indicated at 30 in Figs. 4 and 5, to provide an easier entrance openingfor the cooling air. r l 1 Preferably the notches or gaps between the adjacent ends of corresponding fin portions are of sufilcient size to provide air entrance and exit openings the lateral halves of the circumferential boundaries of which have an area at least as great as the frontal area of the inter-fin spaces at the corresponding side of the cylinder to pro- I vide a free rather than a restricted entrance or exit opening for the cooling air.

The notches separating the two portions of the individual fins may be of the same shape or may be of difierent shapes, as may be found most advantageous in any particular installation, and

the notch shape ,may vary, several different shapes being shown by way of example in Figs. 1, 4 and 5. In Fig. 1 the notchis constituted by a simple partly circular cut out while in Fig. 4 ,it is formed by a V shaped cut out having substantially straight sides and in Fig. 5 it is formed by intersecting circles giving substantially convex end portions to the opposite finportions.

Any one of these various forms or any other form 7 found to be especially advantageousin any particular installation may be used without, in any way exceeding the scope of the invention It is also within the scope of the invention to provide separate fin portions of somewhat less.

than semi-circumferential extent with the adjacent ends of corresponding fin portions at the same side of the cylinderseparated by a space or gap. This construction has particular application where the fins are attached to the cylinder rather than being formed integrally therewith.

In the form'of the invention shown in Fig. 3 the cylinder and fin construction may be the same as that shown in Fig. 1 but in this case the jacket portions 32 and 34 are shown provided with L extensions at the air entrance and air exit locations, the air entrance extension being indicated at 36 and the air exit extension being indicated at 38. The extension 38 may be provided with an outwardly flared or beaded end portion 40 to facilitate the entrance of cooling air or may, if desired, be connected to a suitable cooling air conduit, not illustrated, which may lead from some portion of the airplane such as a wing leading edge, and may include an induction fan if such a feature is desirable. 'The air exit extension 38 may lead into the space within the cowl at the rear of the engine or may, if desired, be connected with a cooling air exhaust collector which may be led to the exterior of the aircraft ferent materials.

aparticular engine installation or may be applied only to those cylinders with which particular difficulty is experienced in obtaining an equal airflow around both sides thereof.

. In additionthe advantages enumerated or inferred above, a further advantage resides in the division of the annular fins into separate portions 'inthat this division relieves stressesin the fin structure, particularly those stresses incident to heat expansion of the cylinders. This advantage maybe found of particular importance where the cy1inder and :fins are formed of 'dif- While a suitable. mechanical embodiment in ,several slightly modified forms has been hereinabove described and illustrated in the accompanying drawing for the purpose of disclosing the invention, it is to be understood thatthe invention is not limited to the particular embodiment so illustrated anddescribed, but that such changes in the size, shapeand arrangement of the various parts may be resorted to as come within the scope-of the sub-joined claims.

Having now described the invention so. that others skilled in the art may clearly understood the same, what it is desired to secure by Letters Patent is as follows:

- 1. Cooling means for an air cooled cylinder comprising, circumferential fins extending outwardly from the exterior surface of said cylinder, said fins being spaced apart in a direction axially of said cylinder, a jacket surrounding said cylinder and said fins and forming with said cyl- .inderv a cooling air passage for directing cooling air over said cylinder and said fins, air entrance and exit openings in said jacket for passing cooling air through said passage, said fins having .cylinder and said fins and forming with said cylinder diametrically, opposed cooling air passages for directing cooling air over said cylinder and said fins, air entrance and exit'openings in said jacket at opposite sides thereof for passing cooling airthrough said passages, said ,fins having cut-away portions immediately underlying each of said openings in said jacket,

and a vane bisecting at least one of said jacket ,openingsandthe respective cut-away portions for dividing the air passingthrough said opening betweensaid opposed cooling air passages.

3. Thearrangement as setforth inclaim 1 in which the edges of at least one of said. jacket openings are curved to facilitate the flow of air into orout of said openings. a

, CHAR S E. LUCKE. 

